The difference between this and the previous tutorial is that in the new version of Angström they introduced a light-weight network manager daemon called connman. On one hand this makes things easier but on the other hand it renders all the old tutorials unusable.

If you would like to extend the capabilities of your Beaglebone you can start by using a USB Serial Converter to reach simple serial devices from USB (hint: you can plug a USB hub on the Beaglebone and use several converter to multiply the serial ports).